1. Field of the Invention
The present invention relates to semiconductor manufacturing process, and more particularly to a connection method for contact holes.
2. Description of the Prior Art
Photolithography processes have been used as essential processes in semiconductor manufacturing procedures. They includes steps of providing a photomask or photomasks having designed patterns such as circuit patterns, doped region patterns, or contact layout patterns and transferring said patterns to a photoresist formed on a substrate by an exposure step and a development step so that those complicated patterns are obtained on the semiconductor chips or on the thin film precisely. After a photolithography process has been carried out, corresponding implantations or etching processes are performed to construct intricate circuit structures.
However, when two or more contact holes are partially overlap in the same thin film, the overlapped regions may be etched several times, thereby influencing the pattern contours, and moreover, damaging others components disposed under the contact plug.